78462421 has 2 divisors, whose sum is σ = 78462422. Its totient is φ = 78462420.

The previous prime is 78462367. The next prime is 78462431. The reversal of 78462421 is 12426487.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 59444100 + 19018321 = 7710^2 + 4361^2 .

It is a cyclic number.

It is not a de Polignac number, because 78462421 - 2¹¹ = 78460373 is a prime.

It is a super-3 number, since 3×78462421³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78462431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39231210 + 39231211.

It is an arithmetic number, because the mean of its divisors is an integer number (39231211).

Almost surely, 2^78462421 is an apocalyptic number.

It is an amenable number.

78462421 is a deficient number, since it is larger than the sum of its proper divisors (1).

78462421 is an equidigital number, since it uses as much as digits as its factorization.

78462421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21504, while the sum is 34.

The square root of 78462421 is about 8857.9016138135. The cubic root of 78462421 is about 428.1085499993.

The spelling of 78462421 in words is "seventy-eight million, four hundred sixty-two thousand, four hundred twenty-one".